Carbon accounting is the systematic measurement of greenhouse gas (GHG) emissions a company produces, expressed in tonnes of CO₂-equivalent (tCO₂e). It follows the globally accepted GHG Protocol Corporate Standard and breaks emissions into three "scopes" — direct, energy-indirect, and value-chain.
Emissions from sources you own or control: factory boilers, company vehicles, process emissions, refrigerant leaks. Typical share: 5–20% of a manufacturer's footprint. Easiest to measure with utility bills and fuel records.
Emissions from purchased electricity, steam, heat, or cooling. Reported using both location-based (grid average) and market-based (contracts) methods. Switching to renewable PPAs or REC certificates from I-REC Standard directly reduces Scope 2.
Everything else across 15 categories: purchased goods, upstream logistics, business travel, product use, end-of-life. Typically 70–90% of a manufacturer's total footprint and the hardest to quantify. Required under CSRD reporting.
For a single facility, 4–6 weeks for Scope 1 & 2; an additional 4–8 weeks for full Scope 3 screening.
For under 5 sites, a well-structured Excel + GHG Protocol calculation tools are sufficient. Software (e.g. Sphera, Watershed, Plan A) becomes essential at multi-site scale or when integrating with ERP.
Location-based uses your country's grid emission factor; market-based reflects your specific energy contracts (renewables count). Both must be reported under the GHG Protocol.